As pointed out by Wang et al. [2], there are difficulties in determination of activity coefficients of reaction species in a constant ionic medium.
Due to the difficulties in determination of reference points for AVR measurement in A&D our own method of SRM was performed on the pre- and postcorrectional ICT scans.
Due to the difficulty in the determination of integral-mean value of gravity along the plumbline, approximations are normally made for practical determination of orthometric heights.
The barrier heights determined by two methods give big difference, which causes the difficulty in the determination of Schottky barrier height.
But they may not be very accurate and may pose difficulty in the determination of inputs for a set of desired outputs (reverse mapping).
The heterogeneous nature of gum samples obtained from the deposits of internal combustion engines is the main difficulty in accurate determination of their metal content.
From the point of view of physics, the use of the internal quantum yield is perfectly justified but faces a difficulty in experimental determination of the photon flux absorbed in the emitter.
We also argue about the lights and shadows related to immune marker use in clinical practice, emphasizing on one hand the importance of their assessment in the choice of therapeutic treatment, on the other, the difficulty in their determination and reproducibility of literature data.
Another reason for the difference may be the difficulty in the determination of the FMCG T wave, its low amplitude waveform shape leading to underestimation of its length.
This situation was worsened by the possible organic residues between crystals, which, to some extent, also led to the difficulty in the determination of the accurate crystal size.
